The objectives of this project are to determine how 2450 MHz microwave radiation interacts with biological material at the cellular level, to observe any effects of this interaction, and to relate the amount of microwave energy absorbed to the effect. The biological system employed in the study is cultured heart cells obtained from 8 day old quail and maintained in culture for two days. In these experiments, the temperature, humidity, and other factors have been carefully monitored in order to eliminate any effects not directly caused by microwave radiation. The design of this exposure system will be completed soon. Experiments are planned for this new test system as soon as the experimental design is completed.